Optimal statistical designs of multivariate EWMA and multivariate CUSUM charts based on average run length and median run leng

Carta kawalan multivariat ialah alat yang berkuasa dalam kawalan proses yang melibatkan kawalan serentak beberapa cirian kualiti yang berkorelasi. Carta-carta multivariat hasil tambah longgokan {MCUSUM) dan multivariat purata bergerak berpemberat eksponen (MEWMA) sentiasa dicadangkan dalam kawalan proses apabila pengesanan cepat anjakan tetap yang keciJ atau sederhana dalam vektor min adalah diingini. A multivariate control chart is a powerful tool in process control involving a simultaneous monitoring of several correlated quality characteristics. The multivariate cumulative sum (MCUSUM) and multivariate exponentially weighted moving average (MEWMA) charts are often recommended in process monitoring when a quick detection of small or moderate sustained shifts in the mean vector is desired

Study on Additional Carrier Sensing for IEEE 802.15.4 Wireless Sensor Networks

Wireless sensor networks based on the IEEE 802.15.4 standard are able to achieve low-power transmissions in the guise of low-rate and short-distance wireless personal area networks (WPANs). The slotted carrier sense multiple access with collision avoidance (CSMA/CA) is used for contention mechanism. Sensor nodes perform a backoff process as soon as the clear channel assessment (CCA) detects a busy channel. In doing so they may neglect the implicit information of the failed CCA detection and further cause the redundant sensing. The blind backoff process in the slotted CSMA/CA will cause lower channel utilization. This paper proposes an additional carrier sensing (ACS) algorithm based on IEEE 802.15.4 to enhance the carrier sensing mechanism for the original slotted CSMA/CA. An analytical Markov chain model is developed to evaluate the performance of the ACS algorithm. Both analytical and simulation results show that the proposed algorithm performs better than IEEE 802.15.4, which in turn significantly improves throughput, average medium access control (MAC) delay and power consumption of CCA detection

A Variable Sampling Interval Multivariate Exponentially Weighted Moving Average Control Chart Based on Median Time-to-Signal

In this study, the median time-to-signal (MTS) is used as an alternative measure to the average time-to-signal (ATS) in evaluating the performance of the variable sampling interval (VSI) multivariate exponentially weighted moving average (MEWMA) chart. Although the ATS is one of the most commonly used performance measures when the sampling interval is varied, it is not an accurate representation of the entire time-to-signal distribution of the VSI charts. Therefore, the percentage points (percentiles) of the time-to-signal distribution are provided for a more comprehensive study of the VSI MEWMA chart. A Monte Carlo simulation is used to calculate the MTS values for various magnitudes of shifts in the process mean vector. The optimal design strategy is to find the charting parameters having the minimum out-of-control MTS (MTS1). A comparison study shows that the VSI MEWMA chart is more effective than the standard MEWMA chart with fixed sampling interval, in detecting shifts in the process mean vector in terms of the MTS

Piperacillin/tazobactam Induced Myelosuppression

Neutropenia, secondary to immune destruction or maturation arrest, is the most commonly described adverse haematological effect of beta-lactam antibiotics. We describe a case of reversible pancytopenia, with evidence of hypocellular marrow, after a prolonged course of piperacillin/tazobactam for 26 days

Molecular epidemiology of Plasmodium vivax and Plasmodium falciparum malaria among Duffy-positive and Duffy-negative populations in Ethiopia

BACKGROUND: Malaria is the most prevalent communicable disease in Ethiopia, with 75% of the country’s landmass classified as endemic for malaria. Accurate information on the distribution and clinical prevalence of Plasmodium vivax and Plasmodium falciparum malaria in endemic areas, as well as in Duffy-negative populations, is essential to develop integrated control strategies. METHODS: A total of 390 and 416 community and clinical samples, respectively, representing different localities and age groups across Ethiopia were examined. Malaria prevalence was estimated using nested PCR of the 18S rRNA region. Parasite gene copy number was measured by quantitative real-time PCR and compared between symptomatic and asymptomatic samples, as well as between children/adolescents and adults from the local community. An approximately 500-bp segment of the human DARC gene was amplified and sequenced to identify Duffy genotype at the -33rd nucleotide position for all the clinical and community samples. RESULTS: Plasmodium vivax prevalence was higher in the south while P. falciparum was higher in the north. The prevalence of P. vivax and P. falciparum malaria is the highest in children compared to adolescents and adults. Four P. vivax infections were detected among the Duffy-negative samples. Samples from asymptomatic individuals show a significantly lower parasite gene copy number than those from symptomatic infections for P. vivax and P. falciparum. CONCLUSIONS: Geographical and age differences influence the distribution of P. vivax and P. falciparum malaria in Ethiopia. These findings offer evidence-based guidelines in targeting malaria control efforts in the country. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12936-015-0596-4) contains supplementary material, which is available to authorized users

Moisture self-regulating ionic skins with ultra-long ambient stability for self-healing energy and sensing systems

Dehydration has been a key limiting factor for the operation of conductive hydrogels in practical application. Here, we report self-healable ionic skins that can self-regulate their internal moisture level by capturing extenral moistures via hygroscopic ion-coordinated polymer backbones through antipolyelectrolyte effect. Results show the ionic skin can maintain its mechanical and electrical functions over 16 months in the ambient environment with high stretchability (fracture stretch ∼2216 %) and conductivity (23.5 mS/cm). The moisture self-regulating capability is further demonstrated by repeated exposures to harsh environments such as 200°C heating, freezing, and vacuum drying with recovered conductivity and stretchability. Their reversible ionic and hydrogen bonds also enable self-healing feature as a sample with the fully cut-through damage can restore its conductivity after 24 h at 40 % relative humidity. Utilizing the ionic skin as a building block, self-healing flexible piezoelecret sensors have been constructed to monitor physiological signals. Together with a facile transfer-printing process, a self-powered sensing system with a self-healable supercapacitor and humidity sensor has been successfully demonstrated. These results illustrate broad-ranging possibilities for the ionic skins in applications such as energy storage, wearable sensors, and human-machine interfaces

Towards engineering heart tissues from bioprinted cardiac spheroids.

Currentin vivoandin vitromodels fail to accurately recapitulate the human heart microenvironment for biomedical applications. This study explores the use of cardiac spheroids (CSs) to biofabricate advancedin vitromodels of the human heart. CSs were created from human cardiac myocytes, fibroblasts and endothelial cells (ECs), mixed within optimal alginate/gelatin hydrogels and then bioprinted on a microelectrode plate for drug testing. Bioprinted CSs maintained their structure and viability for at least 30 d after printing. Vascular endothelial growth factor (VEGF) promoted EC branching from CSs within hydrogels. Alginate/gelatin-based hydrogels enabled spheroids fusion, which was further facilitated by addition of VEGF. Bioprinted CSs contracted spontaneously and under stimulation, allowing to record contractile and electrical signals on the microelectrode plates for industrial applications. Taken together, our findings indicate that bioprinted CSs can be used to biofabricate human heart tissues for long termin vitrotesting. This has the potential to be used to study biochemical, physiological and pharmacological features of human heart tissue

Effect of Tween Series on Growth and cis-9, trans-11 Conjugated Linoleic Acid Production of Lactobacillus acidophilus F0221 in the Presence of Bile Salts

Cis-9, trans-11 conjugated linoleic acid (c9, t11 CLA) producing bacteria have attracted much attention as novel probiotics which have shown beneficial effects on host health. However, bile salts are able to inhibit bacterial growth and c9, t11 CLA production. For recovering growth and c9, t11 CLA production of Lactobacillus acidophilus F0221 in the presence of bile salts, Tween series (Tween 20, Tween 40, Tween 60 and Tween 80) were added in growth culture containing 0.3% oxgall. Results showed that the viable counts were significantly (P < 0.05) recovered to 8.58–8.75 log CFU/mL in the presence of all Tween treatments. However, recovery of c9, t11 CLA production was only demonstrated in the presence of Tween 80 (72.89 μg/mL). Stepwise increasing oxgall in a concentrations range from 0.1% to 0.9% according to human intestinal physiological environments, Tween 80 still showed significant (P < 0.05) recovery ability on growth (8.91–8.04 log CFU/mL) and c9, t11 CLA (69.22–34.27 μg/mL) production. The effect of Tween 80 on growth and production was also investigated in the presence of different types of bile salts (sodium salts of cholic acid (CA), deoxycholic acid (DCA), chendeoxycholic acid (CDCA), glycocholic acid (GCA) and taurocholic acid (TCA)). Results showed that Tween 80 could significantly (P < 0.05) recover c9, t11 CLA production in the presence of all types of bile salts, but the Tween 80 could only significantly (P < 0.05) recover viable counts of the strain in the presence of CA, DCA and CDCA. This recovery ability could be attributed to the protection of leakage of intracellular material. Additionally, although bile salts inhibited growth and c9, t11 CLA production by the growing cell, it promoted the c9, t11 CLA production by the resting cell

Characterization of the Sesbania rostrata Phytochelatin Synthase Gene: Alternative Splicing and Function of Four Isoforms

Phytochelatins (PCs) play an important role in detoxification of heavy metals in plants. PCs are synthesized from glutathione by phytochelatin synthase (PCS), a dipeptidyltransferase. Sesbania rostrata is a tropical legume plant that can tolerate high concentrations of Cd and Zn. In this study, the S. rostrata PCS gene (SrPCS) and cDNAs were isolated and characterized. Southern blot and sequence analysis revealed that a single copy of the SrPCS gene occurs in the S. rostrata genome, and produces four different SrPCS mRNAs and proteins, SrPCS1–SrPCS4, by alternative splicing of the SrPCS pre-mRNA. The SrPCS1 and SrPCS3 proteins conferred Cd tolerance when expressed in yeast cells, whereas the SrPCS2 and SrPCS4 proteins, which lack the catalytic triad and the N-terminal domains, did not. These results suggested that SrPCS1 and SrPCS3 have potential applications in genetic engineering of plants for enhancing heavy metal tolerance and phytoremediation of contaminated soils